Spark-plug.



H. M. SPENCER.

SPARK PLUG.

APPLICATION FILED 11:13.27, 19125 l' l Patented July 29, 1913.

mmf@ W byv Y plug which is readily applied to the usualy separater ernten seams-:Priusmesses.

Speceationof Letters Patent.-

.rateniea mayas, isis.

Applioatiorrled Eebruary 27, 1912Y Serial No. 680,210.`

Be it'knoxvn that jl-{ARRY M. SPENCER, a'citizen ot the United States, residing at- Dunmore, in the countyof Lackaivannazand State of Pennsylvania', have invented anew and. useful SparloPlug, of'ivhich theV following is a specification.

The present invention .relates to improve ments in spark plgs,.th`e primary object of vthe invention Ibeing .the provision of a novel construction and arrangement of sparkingV terminals of a spark plug used inrk connec tion With the jumpsparksystein generally employedin connection with the 'ignitionot' explosive motors, the stem carrying the positive sparking element being disposed for rotation andv provided with a plural-ity of sparking terminals disposed below the sparking terminals of the negativeelement," .so that fthe rotation. of the steincarrying the positive element will automatically clean the` Contact points of both elements Witho'utnthe necessity of theremoval of theplug. fromA the explosive motor. y

A further object of the presentinvention is the' provision of anovel form of spark spark plug receiving receptacles of explosive motors, the negative element of which is projected Within. the explosive or ignition. chamber of `such motor and is provided Withl a 'plurality of downwardly projecting. spark terminals, While disposed concentrically ofl the saine is a stem carrying the positive. sparking terminals,A one to each negative sparking terminal, and so disposed that the greatest possible sparking surfacemay ,be provided, so that a Working spark plug Will he produced, even though a majority of such'y terminals should be carbonized, the said stem. carrying the' positive sparkingA element being so disposed that the `same may be rotated without ythe removal of the plug from the motor, lsuch rotation rotating the positive sparking element so alsltofclean-thefcar- Ahon. adheringto the .negative jandfptositive terminals. 1555] lVith the ,foregoing and other objects in rilewavhich will appear as the description proceeds, the invention resides in 'the combination and arrangement of parts and in the details of construction hereina'ter.'A described and claimed, it ,fleeing understood that changes in thel preciseembgdiinentj:of the invention herein disclosed caiiibe'madewit-hin the scope ot what is claimed Without-dot parting from the spirit ot the invention.

lnmthe drawings Figure l isaf vertical y Central sectional viei'v`o the complete spark plugin the position it assumes when in" op@ Hable-relation With-in an" explosive engine cylinder. F ig. 2 is -afsideelevation ofthe complete lsparkplug reniovedg Fig.l 3 isa bottom plan view ot thefspark plug'. Fig. 4 is aperspeotive Viewfof the' positivesparking-terminals. y j l Referring to the drawings, the' numeral'l l designates the body of the explosivelmotor which` is provided with;- the usualspark plug.

receiving and threaded aperture 2, `for-the reception of the hollowcylindrical vbody 3, which carries the hexagonal metallicnut l of thesparking. plug-.this connection formn ing a ground through the motor.

- Mounted concentricall-y 'within the nut l is porcelain` sleeve 5,' the 4sameektending the full: length of the cylindrical body 3 and above the "same-toA forml thefproper in'- sulationl for the Y 'threaded portion of the body 3 and holding said. :body 3r andl sleeve `5 relatively together, is -a cupgshapedlook niitG. The positive sparking'termjlnil .carrying ste v mountedf eoncentrieally ofthel sleeve 5 and has its lower end disposed below ther sleeve 5, whoseflower face also terminates slightly below the faceofthelo'wer end ofthe nega tivesparking terminal carrying sleeve 3. Mounted upon the` upperend of the porcelain sleeve 5 and surrounding the adjacent portion ofthe stem 7 but out of' Contact therewith, is ametal cap or disk," which' held relatively to thesleeve ,against rotation therefrom p or. eap- 8 is provided with the concentric receptacle 10 for the reeeptiolni 1of a coiled spring ,11, which rests upon'theupper end of the porcelain sleeve` 5 andfbears nponthe under side of the-metalA disk 12,'-Which is held relatively upon the-stem? androtatable therewith.- by means of the -s'et scre'w'fl. The disks 8 and .12 are-'provided lWiththe,indicati-ng 'marks 14t-v and 153 respeetively, Which as shown `in Fig. l indieatejthat the spark ingterminals ofthe plugarein proper position for producing the vmzmiinum'- spark, the stem beingso mounted that the'same may be rotatedto the right'or-left, as viewed in Fig. l, to' throws7l the said `marks 14 and lout. ofV alinementand indicate to the op erator.` the positioning of .the sparking ter minals,as will 'later appe'arlI Adj-ustably mounted l upon the stem 7 abovethedisk l2, is a looking milled disk 16 plug. Fitted uponthe m or rod 7-is by meansof 'a 'screW'Q'A "This disk which with the disk 12 provides a means for clamping' the terminal plates 17 of the positive conductor therebetween so that the current is properly conducted to the stem 7 and the sparking' terminals thereof.

ln order to rotate the stem without the necessity ofy removing' the spark plugs from the motor cylinder, the milled disk 18 provided with the shouldered portion 19 is fitted upon the extreme upper end of the stem 7 above, the milled disk 16, the pin 20 being so disposed as to rigidly secure the saine in position so that the stein 7 may be rotated either by the oscillation through the milled disk 1S or by means of a wrench placed upon the shouldered projection 19.

Foi-med integral with and projecting; from the lower end of the cylinder 3, said cylinder 3 formingthe negative element of the spark plug, are the negative sparking' terminals 21, each one of which is disposed at a quadrant about the circumference, as illustrated in Fin. 3 and is provided with thelower inclined or beveled portion b, while keyed upon and carried by the lower end of the stein 7, is a disk 22 of a lesser diameter than the lower end of the porcelain sleeve 5, said disk being held upwardly and in engagement with the lower end of the said sleeve by means of the spring 11,

and carrying the radially disposed positive is sparking terminals 23, each one of which disposed to coact with the. negative sparking terminals 21 and is provided with the upper inclined beveled portion b whichco-l acts with the beveled portion a of the terminals 21, so that the rotation of the stem 7 in the direction of the arrow Fig. 3, will cause the sparking; terminals QB to ride. upon the beveled portion of the sparking terminals 21, such 'riding due to the spring 11, producing sufficient friction to cut the carbon from the terminals 21 and thus permitting' the terminals 23 to be snapped over the terminals 21 to assume any of the positions that will produce the maximum spark. or as shown in dotted lines Fil. 3. It will thus be seen that the terminals 23 are rotated without the necessity of the removal of the plug from the motor and that all of the terminals may be properly positioned by means of the indicating marks 14: and 15, the relative location of the saine indicating visually the positioning,r of the positive terminals relatively to the. negative terminals. The. adjacent spark ;jap forming faces of the pairs of terminals Q1-23, are inclined. and when in proper sparking' relation are separated, the lower end of the insulating body, 5, holding the terminals 23, by means of its engagement with the disk Q2, out of Contact with the terminals Q1 and also the lower end of the bushing 8. Thus when the disk 22 is'rotated, the inclined surfaces a ride upon each other and the accumulated carbon is scraped from both surfaces, so that the terminals are cleaned without the removal of the plugr from the engine cylinder.

What is claimed is:

4 1. A spark plug, having' a cylindrical metallic body, a plurality of'downwardly projecting sparking `terminals carried upon 'the lower end of said cylindrical body, an 'insulating body of greater length than the metallic body mounted concentrically'of and within the metallic body and having its lower end disposed to project slightly below the lower facial plane of the lower end of the metallic body, a rod mounted rotatably and?concentrically of the insulating body, the upper end thereof projecting beyond the upper end of the insulating` body, a sparking` terminal carrying' member disposed upon the lower end of said rod below the cylindrical and insulating' bodies, the same being provided with a similar number of sparking terminals to that of the metallic body, the sparking` terminals of both elements being of such a size as when disposed in radial alinement. to contact, whereby the rotation of the rod will clean the sparking7 terminals of both elements, and a spring mounted upon the upper cud of the rod and insulating:- body to hold the sparking ter ininal carryingY member of the rod resiliently against. the under side of the insulatinnY body.

2. A spark plug, including a .metal busliin; having a plurality of sparkingterminals with lower inclined faces projecting from its lower end, a sleeve of insulation disposed within tlie bushing' and having its lower end 'projecting slight-ly below* the lower end of the bushingi but within the facial plane of the terminals. a stem mounted for sliding` and rotary movement within the sleeve, a plurality of radial sparkingterminals, one to each terminal of the bushing, mounted upon the lower end of the stem and limited against inward movement by the lower end of the insulating sleeve, each y radial terminal beinel provided lwith an inclined face for scraping action to clean the terminals of the bushing andfor adjustment therewith to produce a spark gap between the terminals, and a spring for hold- .ineV the stem and radial terminals in' such position. Y j

In testimony that I claim the foregoing as my own, I have hereto atlixed my signature in the presence of two witnesses.

HARRY MARVIN SPENCER. Witnesses M. J. MURRAY, Jr., C. T. SHiNnnL. 

